Abstract: The present disclosure is directed to a method for manufacturing a micro-electro-mechanical device. The method includes the steps of forming, on a substrate, a first protection layer of crystallized aluminum oxide, impermeable to HF; forming, on the first protection layer, a sacrificial layer of silicon oxide removable with HF; forming, on the sacrificial layer, a second protection layer of crystallized aluminum oxide; exposing a sacrificial portion of the sacrificial layer; forming, on the sacrificial portion, a first membrane layer of a porous material, permeable to HF; forming a cavity by removing the sacrificial portion through the first membrane layer; and sealing pores of the first membrane layer by forming a second membrane layer on the first membrane layer.

Abstract: Method for manufacturing a micro-electro-mechanical system, MEMS, integrating a first MEMS device and a second MEMS device. The first MEMS device is a capacitive pressure sensor and the second MEMS device is an inertial sensor. The steps of manufacturing the first and second MEMS devices are, at least partly, shared with each other, resulting in a high degree of integration on a single die, and allowing to implement a manufacturing process with high yield and controlled costs.

Abstract: A micromechanical mirror structure includes a mirror element designed to reflect an incident light radiation and a protective structure arranged over the mirror element to provide mechanical protection for the mirror element and to increase the reflectivity of the mirror element with respect to the incident light radiation. The protective structure has a first protective layer and a second protective layer which are stacked on the mirror element. The second protective layer is arranged on the first protective layer and the first protective layer is arranged on the mirror element. The layers include a respective dielectric material and having respective refractive indexes that jointly increase the reflectivity of the mirror element in a range of wavelengths of interest.

Abstract: A MEMS acoustic transducer provided with: a substrate of semiconductor material, having a back surface and a front surface opposite with respect to a vertical direction; a first cavity formed within the substrate, which extends from the back surface to the front surface; a membrane which is arranged at the upper surface, suspended above the first cavity and anchored along a perimeter thereof to the substrate; and a combfingered electrode arrangement including a number of mobile electrodes coupled to the membrane and a number of fixed electrodes coupled to the substrate and facing respective mobile electrodes for forming a sensing capacitor, wherein a deformation of the membrane as a result of incident acoustic pressure waves causes a capacitive variation of the sensing capacitor. In particular, the combfingered electrode arrangement lies vertically with respect to the membrane and extends parallel thereto.

Abstract: A micromechanical mirror structure includes a mirror element designed to reflect an incident light radiation and a protective structure arranged over the mirror element to provide mechanical protection for the mirror element and to increase the reflectivity of the mirror element with respect to the incident light radiation. The protective structure has a first protective layer and a second protective layer which are stacked on the mirror element. The second protective layer is arranged on the first protective layer and the first protective layer is arranged on the mirror element. The layers include a respective dielectric material and having respective refractive indexes that jointly increase the reflectivity of the mirror element in a range of wavelengths of interest.

Abstract: A MEMS acoustic transducer provided with: a substrate of semiconductor material, having a back surface and a front surface opposite with respect to a vertical direction; a first cavity formed within the substrate, which extends from the back surface to the front surface; a membrane which is arranged at the upper surface, suspended above the first cavity and anchored along a perimeter thereof to the substrate; and a combfingered electrode arrangement including a number of mobile electrodes coupled to the membrane and a number of fixed electrodes coupled to the substrate and facing respective mobile electrodes for forming a sensing capacitor, wherein a deformation of the membrane as a result of incident acoustic pressure waves causes a capacitive variation of the sensing capacitor. In particular, the combfingered electrode arrangement lies vertically with respect to the membrane and extends parallel thereto.

Abstract: A micromechanical structure for a MEMS capacitive acoustic transducer, has: a substrate made of semiconductor material, having a front surface lying in a horizontal plane; a membrane, coupled to the substrate and designed to undergo deformation in the presence of incident acoustic-pressure waves; a fixed electrode, which is rigid with respect to the acoustic-pressure waves and is coupled to the substrate by means of an anchorage structure, in a suspended position facing the membrane to form a detection capacitor. The anchorage structure has at least one pillar element, which is at least in part distinct from the fixed electrode and supports the fixed electrode in a position parallel to the horizontal plane.

Abstract: A micromechanical structure for a MEMS capacitive acoustic transducer, has: a substrate made of semiconductor material, having a front surface lying in a horizontal plane; a membrane, coupled to the substrate and designed to undergo deformation in the presence of incident acoustic-pressure waves; a fixed electrode, which is rigid with respect to the acoustic-pressure waves and is coupled to the substrate by means of an anchorage structure, in a suspended position facing the membrane to form a detection capacitor. The anchorage structure has at least one pillar element, which is at least in part distinct from the fixed electrode and supports the fixed electrode in a position parallel to the horizontal plane.